:root{
    --bg: #f5f7fa;
    --viewer-bg: #ffffff;
    --surface: #ffffff;
    --surface-2: #f8f9fa;
    --surface-3: #f0f0f0;
    --border: #e0e0e0;
    --border-strong: #d0d0d0;
    --btn-edge: rgba(0,0,0,.08);
    --btn-glow: 0 0 5px rgba(0,0,0,.08);
    --btn-glow-hover: 0 0 7px rgba(0,0,0,.12);
    --text: #333333;
    --text-2: #555555;
    --text-3: #888888;
    --accent: #e94560;
    --accent-hover: #c73e54;
    --accent-dim: rgba(233,69,96,0.10);
    --danger: #ef4444;
    --success: #22c55e;
    --gutter: 16px;
    --panel-w: 420px;
}

*{box-sizing:border-box;margin:0;padding:0}
html,body{height:100%;overflow:hidden;background:linear-gradient(135deg, #f5f7fa 0%, #e4e8ec 100%);color:var(--text);font-family:system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,sans-serif;font-size:13px;line-height:1.5;-webkit-font-smoothing:antialiased}
body{display:flex;flex-direction:column}
button,input,select{font-family:inherit;color:inherit}
button{cursor:pointer;border:none;background:none}

.container{flex:1 1 0;min-height:0;display:flex;flex-direction:column;max-width:1400px;width:100%;margin:0 auto;padding:0 15px}

.page-header{flex:0 0 auto;text-align:center;padding:12px 0 10px}
.page-header .back-link{display:inline-block;margin-bottom:6px;font-size:.8rem;color:var(--accent);text-decoration:none}
.page-header .back-link:hover{text-decoration:underline}
.page-header h1{font-size:1.7rem;background:linear-gradient(90deg,#e94560,#c73e54);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin-bottom:4px;font-weight:700}
.page-header p{color:#666;font-size:.95rem}
.page-header .downloads-count{font-size:.8rem;color:#888;margin-top:4px;display:inline-flex;align-items:center;gap:4px}

.app{flex:1 1 0;min-height:0;min-width:0;display:grid;grid-template-rows:56px 1fr;background:var(--viewer-bg);border-radius:12px;box-shadow:0 4px 20px rgba(0,0,0,.06);overflow:hidden;margin-bottom:14px}

.app-header{position:relative;display:flex;align-items:center;justify-content:space-between;padding:0 var(--gutter);gap:16px;flex-wrap:nowrap}
.app-header::after{content:"";position:absolute;left:var(--gutter);right:var(--gutter);bottom:0;height:1px;background:var(--border);pointer-events:none}

.brand{display:flex;align-items:center;gap:12px;min-width:0;flex:0 1 auto;overflow:hidden;padding-left:8px}
.brand-logo{height:22px;display:inline-flex;align-items:center;font-family:system-ui,sans-serif;font-weight:800;font-size:23px;letter-spacing:-.3px;line-height:1;user-select:none}

.header-actions{display:flex;gap:8px;align-items:center}

.btn{height:32px;padding:0 14px;border-radius:6px;font-size:12px;font-weight:500;display:inline-flex;align-items:center;gap:6px;letter-spacing:.01em;transition:all .15s ease;background:var(--surface-2);border:1px solid var(--border);color:var(--text-2)}
.btn:hover{background:var(--surface-3);color:var(--text);border-color:var(--border-strong)}
.btn:disabled{opacity:.55;cursor:not-allowed;background:var(--surface-2);color:var(--text-3);border-color:var(--border)}
.btn-primary{background:var(--accent);color:#fff;border-color:var(--accent);font-weight:600}
.btn-primary:hover{background:var(--accent-hover);border-color:var(--accent-hover)}
.btn-primary:disabled{background:var(--surface-3);color:var(--text-3);border-color:var(--border)}
.btn-outline{background:transparent}
.btn-badge{background:var(--surface-2);border-color:var(--border-strong)}
.btn-badge svg{color:var(--accent)}

.main{position:relative;display:block;height:100%;min-height:0;min-width:0}

.iconbar{position:absolute;top:0;bottom:0;left:0;width:52px;z-index:3;display:flex;flex-direction:column;align-items:center;padding:10px 0;gap:8px;background:var(--surface-2);border-right:1px solid var(--border)}
.iconbar .icon{width:36px;height:36px;border-radius:8px;display:flex;align-items:center;justify-content:center;color:var(--text-3);transition:all .15s;cursor:pointer;background:transparent;border:none}
.iconbar .icon:hover{background:var(--surface-3);color:var(--text)}
.iconbar .icon.active{background:var(--accent-dim);color:var(--accent)}

.panel{position:absolute;top:0;bottom:0;left:52px;width:calc(var(--panel-w) - 52px);z-index:2;background:var(--surface);border-right:1px solid var(--border);display:flex;flex-direction:column;overflow:hidden;pointer-events:auto}
.panel .section{display:none;flex-direction:column;min-height:0;flex:1}
.panel .section.active{display:flex}

.panel-header{flex:0 0 auto;display:flex;align-items:center;justify-content:space-between;padding:14px 18px 12px;border-bottom:1px solid var(--border)}
.panel-title{font-size:11px;font-weight:600;text-transform:uppercase;letter-spacing:.12em;color:var(--text-3);display:inline-flex;align-items:center;gap:9px}
.panel-title span{width:20px;height:20px;border-radius:50%;background:var(--accent);color:#fff;display:inline-flex;align-items:center;justify-content:center;font-size:11px;font-weight:700}

.section-body{flex:1;overflow-y:auto;padding:16px 18px;display:flex;flex-direction:column;gap:16px}

.viewport{position:absolute;top:0;right:0;bottom:0;left:var(--panel-w);z-index:1;background:var(--viewer-bg);overflow:hidden}
.viewport-placeholder{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;color:var(--text-3);gap:12px;text-align:center;padding:20px}
.viewport-placeholder p{font-size:14px}
.viewport-loading{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:rgba(255,255,255,.85);color:var(--text-2);font-weight:500;z-index:10}

.slice-progress{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:rgba(255,255,255,.9);z-index:20}
.slice-progress-box{width:min(320px,80%);background:var(--surface);border:1px solid var(--border);border-radius:12px;padding:24px;box-shadow:0 10px 40px rgba(0,0,0,.12);display:flex;flex-direction:column;align-items:center;gap:14px;text-align:center}
.slice-progress-spinner{width:36px;height:36px;border:3px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin 1s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}
.slice-progress-label{font-size:15px;font-weight:600;color:var(--text)}
.slice-progress-bar{width:100%;height:8px;background:var(--surface-2);border-radius:4px;overflow:hidden}
.slice-progress-fill{height:100%;width:0%;background:var(--accent);border-radius:4px;transition:width .3s ease}
.slice-progress-stage{font-size:12px;color:var(--text-2)}

.dropzone{margin:0;border:2px dashed var(--border);border-radius:10px;padding:32px 16px;text-align:center;cursor:pointer;background:var(--surface-2);transition:all .15s;display:flex;flex-direction:column;align-items:center;color:var(--text-2)}
.dropzone:hover,.dropzone.dragover{border-color:var(--accent);background:var(--accent-dim);color:var(--text)}
.dropzone strong{font-size:13px;margin-bottom:4px}
.dropzone span{font-size:11px;opacity:.8}

.file-info{background:var(--surface-2);border:1px solid var(--border);border-radius:8px;padding:14px;font-size:12px;color:var(--text-2);display:flex;flex-direction:column;gap:6px}
.file-info strong{color:var(--text)}

.field{display:flex;flex-direction:column;gap:8px}
.field-label{font-size:12px;font-weight:500;color:var(--text-2)}
.field-label.field-check{display:flex;align-items:center;gap:8px;cursor:pointer}
.field-label.field-check input{width:16px;height:16px;accent-color:var(--accent)}
.field-head{display:flex;justify-content:space-between;align-items:center}
.field-value{font-size:12px;font-weight:600;color:var(--text)}

.select{height:36px;padding:0 10px;border-radius:6px;border:1px solid var(--border);background:var(--surface-2);font-size:13px;outline:none}
.select:focus{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-dim)}

.slider{width:100%;height:6px;border-radius:3px;background:var(--border);outline:none;-webkit-appearance:none;appearance:none}
.slider::-webkit-slider-thumb{-webkit-appearance:none;width:16px;height:16px;border-radius:50%;background:var(--accent);cursor:pointer;border:2px solid #fff;box-shadow:0 1px 3px rgba(0,0,0,.2)}
.slider::-moz-range-thumb{width:16px;height:16px;border-radius:50%;background:var(--accent);cursor:pointer;border:2px solid #fff;box-shadow:0 1px 3px rgba(0,0,0,.2)}

.result-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.result-card{background:var(--surface-2);border:1px solid var(--border);border-radius:8px;padding:14px;text-align:center}
.result-label{font-size:10px;text-transform:uppercase;letter-spacing:.08em;color:var(--text-3);margin-bottom:6px}
.result-value{font-size:18px;font-weight:700;color:var(--text)}
.result-value .unit{font-size:12px;font-weight:500;color:var(--text-3);margin-left:2px}
.result-empty{color:var(--text-3);text-align:center;padding:30px 10px;font-size:13px}

.transform-panel{background:var(--surface-2);border:1px solid var(--border);border-radius:8px;padding:14px;display:flex;flex-direction:column;gap:14px}
.axis-buttons{display:flex;gap:6px;margin-top:4px}
.axis-inputs{display:flex;gap:8px;flex-wrap:wrap}
.axis-input{display:flex;align-items:center;gap:4px;background:var(--surface);border:1px solid var(--border);border-radius:5px;padding:4px 6px;flex:1;min-width:70px}
.axis-input .axis-label{font-size:10px;font-weight:700;color:#fff;background:var(--accent);border-radius:3px;padding:2px 5px}
.axis-input input{width:50px;border:none;background:transparent;font-size:13px;color:var(--text);outline:none;text-align:right}
.transform-actions{display:flex;flex-wrap:wrap;gap:8px}
.transform-actions .btn{flex:1;min-width:120px;justify-content:center}
.face-hint{font-size:11px;color:var(--text-3);line-height:1.5;background:var(--surface);border:1px dashed var(--border);border-radius:6px;padding:10px}
.face-buttons{display:flex;flex-wrap:wrap;gap:6px}
.face-buttons .btn-mini{flex:1;min-width:60px;justify-content:center}
.face-status{font-size:11px;color:var(--accent);background:var(--accent-dim);border:1px dashed var(--accent);border-radius:6px;padding:8px;text-align:center;margin-top:6px}
.face-status.active{background:#fff7f8}

.bed-ruler{position:absolute;left:18px;right:18px;bottom:14px;z-index:5;pointer-events:none;user-select:none}
.bed-ruler-line{height:1px;background:linear-gradient(90deg, rgba(0,0,0,.25) 0%, rgba(0,0,0,.25) calc(100% - 8px), transparent calc(100% - 8px));background-size:100% 100%;position:relative}
.bed-ruler-line::before,.bed-ruler-line::after{content:"";position:absolute;top:-3px;width:1px;height:7px;background:rgba(0,0,0,.35)}
.bed-ruler-line::before{left:0}
.bed-ruler-line::after{right:8px}
.bed-ruler-labels{display:flex;justify-content:space-between;margin-top:3px;font-size:11px;color:rgba(0,0,0,.55);font-weight:500}

#viewport{cursor:default}
#viewport.pick-face-mode{cursor:crosshair}
#viewport.pick-face-mode canvas{outline:2px dashed var(--accent);outline-offset:-2px}

.toast{position:fixed;bottom:20px;right:20px;z-index:1000;padding:12px 18px;border-radius:8px;background:var(--text);color:#fff;font-size:13px;box-shadow:0 4px 15px rgba(0,0,0,.2);animation:toastIn .2s ease}
.toast.error{background:var(--danger)}
.toast.success{background:var(--success)}
.toast.info{background:var(--accent)}
@keyframes toastIn{from{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}

footer{flex:0 0 auto;text-align:center;padding:10px 0;font-size:.85rem;color:#888}
footer a{color:var(--accent);text-decoration:none}
footer a:hover{text-decoration:underline}

@media (max-width: 900px){
    :root{--panel-w: 100%}
    .app{grid-template-rows:auto 1fr}
    .app-header{flex-wrap:wrap;height:auto;padding:10px var(--gutter);gap:10px}
    .brand{padding-left:0}
    .header-actions{width:100%;justify-content:flex-end}
    .main{display:flex;flex-direction:column}
    .iconbar{position:relative;top:auto;bottom:auto;left:auto;width:100%;flex-direction:row;justify-content:center;border-right:none;border-bottom:1px solid var(--border);padding:8px}
    .panel{position:relative;top:auto;bottom:auto;left:auto;width:100%;border-right:none;max-height:50vh}
    .viewport{position:relative;top:auto;right:auto;bottom:auto;left:auto;flex:1;min-height:300px}
}